1. Field of the Invention
The invention relates to an energy adjustor, and more particularly to an energy adjustor method for a fuel cell group.
2. Description of the Related Art
Given the decrease of non-renewable energy sources, it is important to develop new energy sources. Fuel cells are new energy sources. The environment is not contaminated by the fuel cells. The fuel cells have high efficiency. Thus, the fuel cells can solve the difficult problem of energy deficiency in the world. The transforming efficiency of the fuel cells is high and the environment is not contaminated by the fuel cells. The size of the fuel cells is small and the fuel cells can be conveniently utilized in any place.
However, fuel cells cannot continuously output a stable voltage. Generally, when fuel cells output large currents, the voltage of the fuel cells is reduced. Thus, the voltage range of the fuel cells is wide and exceeds the working range of an electric appliance. Furthermore, the response of the fuel cells is not good. Since the fuel cells are easily affected upon a chemical reaction, the fuel cells have a time delay problem. When a load driven by the fuel cells is frequently turned on or turned off or the load is temporary driven, if the fuel cells cannot provide power to the load, the loading of the fuel cells is too heavy. Thus, the efficiency of the fuel cells is obviously reduced.
Thus, the fuel cells are applied with a power converter to adjust, control and manage the power provided by the fuel cells. For the fuel cells, the power converter is an important issue and relates to quality, safety and reliability of a power system utilizing the fuel cells.
However, a conventional power converter utilizes switches to switch the output power of the fuel cells to drive a load. No device adjusts the property of the fuel cells. Additionally, the input voltage range of the conventional power converter is narrow. Thus, the conventional power converter only receives a narrow input voltage and cannot match the fuel cells with large output voltage ranges.
In addition, the output voltage of the conventional power converter is fixed and converting efficiency, accuracy and stability of the conventional power converter are low. Thus, the conventional power converter cannot accurately and quickly control the output of the fuel cells.